Screaming LM386: An Audio Amplifier with PCB Art

Beautiful project from Frank Milburn on element14:

Intro_Cartoon

Screaming LM386: An Audio Amplifier with PCB Art

I decided to give PCB art a try and will be basing my attempt on methods described by Andrew Sowa.  Andrew uses Adobe Illustrator for the art work and KiCad for the PCB design.  I will also use KiCad but will use my trusty pre-subscription version of Photoshop for the artwork.  Inkscape is another possibility.  Andrew’s process is described in this video from which my work is derived.  The detail behind many of the steps won’t be described in this post – watch the video for that.

The goal is to take a photograph, painting, etc. and place it on a PCB using the FR4, copper layer, solder mask, and silk screen to make the palette.  My PCB will feature the famous work by Edvard Munch, The Scream which has always fascinated me.  So, how to turn a masterpiece into a PCB facsimile?

Screenshot from 2020-02-20 12-40-07

Palette

The limited palette is a challenge.  For this exercise the focus will be on the central figure in order to reduce board size (and thus cost) of the experiment.  The OSHPark purple solder mask will hopefully give the dark colors desired.  Andrew also used OSHPark in his example, and helpfully provided a palette which has been modified here to help describe how the layers translate to color and are stacked for conversion in KiCad.

Palette

There is a shared project for the board:

 

Screenshot from 2020-02-20 12-35-07

And watch it on YouTube:

Screaming LM386: An Audio Amplifier with PCB Art

Build a Cracklebox in Berlin

“Your skin is a circuit”

Build a Cracklebox with Nicolas Collins on Feb. 17th at Common Ground in Berlin:
Screenshot from 2020-02-06 12-49-44

Back in December, I visited Nicolas Collins at the School of the Art Institute in Chicago and got to see one of the latest creations that he is using in class. The beautiful traces wind their way into the classic LM386 audio amp for an expressive overdriven effect:

Nicolas Collins is well known for having written Handmade Electronic Music: The Art of Hardware Hacking:

Screenshot from 2020-01-15 11-38-09.png

provides a long-needed, practical, and engaging introduction to the craft of making – as well as creatively cannibalizing – electronic circuits for artistic purposes. With a sense of adventure and no prior knowledge, the reader can subvert the intentions designed into devices such as radios and toys to discover a new sonic world. At a time when computers dominate music production, this book offers a rare glimpse into the core technology of early live electronic music, as well as more recent developments at the hands of emerging artists. In addition to advice on hacking found electronics, the reader learns how to make contact microphones, pickups for electromagnetic fields, oscillators, distortion boxes, and unusual signal processors cheaply and quickly.

 

Build a Cracklebox in Berlin

Handmade Electronic Music with Nicolas Collins

Back in December, I visited Nicolas Collins at the School of the Art Institute in Chicago and got to see one of the latest creations that he is using in class. The beautiful traces wind their way into the classic LM386 audio amp for an expressive overdriven effect:

Nicolas Collins is well known for having written Handmade Electronic Music: The Art of Hardware Hacking:

Screenshot from 2020-01-15 11-38-09.png

provides a long-needed, practical, and engaging introduction to the craft of making – as well as creatively cannibalizing – electronic circuits for artistic purposes. With a sense of adventure and no prior knowledge, the reader can subvert the intentions designed into devices such as radios and toys to discover a new sonic world. At a time when computers dominate music production, this book offers a rare glimpse into the core technology of early live electronic music, as well as more recent developments at the hands of emerging artists. In addition to advice on hacking found electronics, the reader learns how to make contact microphones, pickups for electromagnetic fields, oscillators, distortion boxes, and unusual signal processors cheaply and quickly.

Handmade Electronic Music with Nicolas Collins

OKAY 2 Monophonic Synth Kit

 writes on the Tindie blog:

okay2-Medium

OKAY 2 Monophonic Synth Kit

Take a look at Tindie’s thriving sound section and you’ll see there is no shortage of people making their own electronic music. These devices take many forms, and one interesting take on sound creation is the OKAY 2 Synth DIY Kit. At face value it features 2 octaves of keys, a built-in amplifier along with a 1/4″ line out, and knobs to select the octaves that you’d like to play — but it gets more interesting under the hood.

Oskitone OKAY 2 from oskitone on Vimeo.

What makes it unique by today’s standards is that it doesn’t use any sort of computer or microcontroller, but instead produces sound using an LM555 timer along with other discreet components for monophonic sound. Given its small size, you could use two at once, perhaps combining them via the line out to be further modified in your synth setup!

In case you’re wondering, the original—or nearly so as it’s version 1.1.1—OKAY is also available. It works largely the same as the OKAY 2, but features only a single octave of keys, and doesn’t have an audio output jack.

OKAY 2 Monophonic Synth Kit

4CHord MIDI

From Sven Gregori on Hackaday.io:

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the USB MIDI keyboard dedicated to play all the four chord songs, from Adele via Green Day and Red Hot Chilli Peppers to U2 and Weezer. Thanks to MIDI, you can be any instrument – and all of them at once. Yay!
 Built around an AVR ATmega328 and Objective Development’s V-USB library, 4chord MIDI acts as a regular USB MIDI instrument. It supports playback in every key and five different playback modes:
  • simple triad chord (root, third, fifth)
  • triad chord + third + fifth + third as quarter notes
  • triad chord + third + fifth + octave as quarter notes
  • root note + third + fifth + third as quarter notes
  • root note + third + fifth + octave as quarter notes

The playback tempo can be set between 60 and 240 bpm.

Here is the board in action:

The design files and source code are available on GitHub:

sgreg/4chord-midi

4CHord MIDI

Dooba.io open source MP3 player

MP3 player design from Dooba.io:

Shiva: MP3 player for the masses

Based on the ioNode, Aecho and Nomad modules, the Shiva allows browsing & playing MP3 files stored on any FAT-formatted MicroSD card with audio quality up to 128Kbps.

Screenshot from 2017-07-11 11-27-48.png

The actual Shiva board itself is quite simple, featuring an MCP23008 from Microchip for reading the 7 buttons, a DM3D-SF MicroSD card socket from Hirose and a 128×64 OLED display from Adafruit.

IMG_0327

To keep everything neatly together I needed an enclosure. Being lucky enough to own a half-decent 3D printer I decided to keep things minimal but functional. Who needs glue and screws when you can go for a press-fit case?

IMG_0346The code for the Shiva MP3 player is available in the Dooba Firmware SDK under /src/shiva.  Schematic and board are available in the Dooba Hardware collection.

Dooba.io open source MP3 player

The Monolith Brings the Boom to Maker Faire

[Ross Fish], [Darcy Neal], [Ben Davis], and [Paul Stoffregen] created “the Monolith”, an interactive synth sculpture designed to showcase capabilities of the Teensy 3.6 microcontroller. The Monolith consists of a clear acrylic box covered in LED-lit arcade buttons. The forty buttons in front serve as an 8-step sequencer with five different voices, while touch sensors on the left…

via The Monolith Brings the Boom to Maker Faire — Hackaday

The Monolith Brings the Boom to Maker Faire

Multifunction Raspberry Pi Chiptune Player

General Instrument’s AY-3-8910 is a chip associated with video game music and is became popular with arcade games and pinball machines. The chip tunes produced by this IC are iconic and are reminiscent of a great era for electronics. [Deater] has done an amazing job at creating a harmony between the old and new with his Raspberry…

via Multifunction Raspberry Pi Chiptune Player — Hackaday

Multifunction Raspberry Pi Chiptune Player

I/O Expander for LED Arcade Buttons

Teensy creator Paul Stoffregen has shared a new project on OSH Park:

I/O Expander for LED Arcade Buttons

The Monolith Synth Project needed to use a large number of these LED lit arcade buttons.

Dimming of the LEDs was required. Initially I considered using this Adafruit 16 Channel PWM board. But the LEDs in these buttons have integrated resistors which require 12 volts, so 16 transistor circuits and another board for reading the switches would have also been needed.

It uses the same PCA9685 chip for 12 bit PWM control on every LED, with mosfet drivers to handle 12V outputs, and also a MCP23017 chip to read the buttons. Every button has a discrete 1K pullup resistor (rather than using the higher impedance on-chip pullups) to help with use in the same cable bundles cross coupling to 12V PWM signals.

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Order from OSH Park

Monolith Synth

Four of these boards where used in the Monolith Synth project:

monolith_before_mf

The project is featured in this Tested video:

I/O Expander for LED Arcade Buttons